The A-League and W-League finals will be patrolled by even more sets of eyes after Football Federation Australia (FFA) announced goal line officials will preside over the matches.
The extra officials will be positioned at either end of the field to assist referees with decisions in and around the penalty area including penalties and goals.
A-League chief executive Damien de Bohun said goal-line referees had been involved in getting crucial decisions right when they were trialed in the FFA Cup.
"The technical standard and speed of play in the A-League goes up every season and this places additional demands on match officials," de Bohun said.
"Referees continue to improve as well thanks to additional coaching and fitness programs but in the split-second available to make decisions in and around the penalty area the extra set of eyes is extremely valuable."
The outspoken Arnold used a post-match media conference on January 3 to make a plea for more whistleblowers.
"My opinion is they have to put in goal line referees immediately," Arnold said after Sydney FC's 2-2 draw with Melbourne City.
"If you had goal-line referees, another two sets of eyes, it can help."
Referee Ben Williams apologised publicly for two mistakes in a 0-0 draw between Adelaide United and Western Sydney Wanderers on New Year's Day, while Central Coast striker Roy O'Donovan remained on the field after head-butting Manny Muscat, an act which later drew an eight-match suspension.
"The reason I'm speaking out is because it costs coaches jobs," Arnold said.
"If you have goal line referees, they're there, they can see everything."
The FFA has also made a submission to FIFA about a trial of video replays to assist officials.